smith



(No Model.)

C. H. SMITH.

AXLB BOX. No. 303,954. Patented Aug. 19, 1884.

UNiTED Srarns hir-resi* CHARLES II. SMITH, CF XOREOLK, CONNECTICUT, ASSIGNCR OF ONE-HALF TO ELLSWCRTH D. IVES, OF SAME PLACE.

AXLE-BOX.

SPECIFICATION forming part of Letters Patent No. 303,954, dated August 19, 1884.

Application tiled December 20, 18S3. (No model.)

To @ZZ whom it 17mg/ concern,.-

Ile it known that I, Cuanms H. SMITH, of Norfolk, in the county of Litchfield and State of Connecticut, have invented a certain new and useful Improvement Per-taining to Axle Boxes, of which the following is a description, reference being had to the accompanying drawing, where the figure' is a view in central vertical longitudinal section of an axle bor: constructed in accordance with my invention.

My improvement relates to the class of axleboxes in common use on vehicles; and it consists in an axle-box made of a peculiar matcrial not heretofore employed for the same or an analogous use and in a special. and particw lar way.

For many years efforts have been made by manufacturers to produce an axle-box that should be durable and comparatively inexpensive, and to that end boxes have been made of cast gray iron that meet the end of cheapness, but are bulky, (to gain strcngth,) fragile, and so soft as to be quickly worn out. Malleable-irou boxes have been made, and have, in like manner with the cast-iron, been case-hardened, with the undesirable result of brittlcness and lack of homogeneity, presence of sand streaks, and blow holes. \Vroughtmetal tubes have been drawn and then upset to shape an axle-box, and then case-hardened, but the fibrous nature of the material when soft, and great brittleness after hardening, have been serious defects; but a great objection is the large cost of axle-boxes of this latter construction. High-grade steel (that in which a large percentage oi' carbon is present in. the alloy) has been tried experimentally; but the excessive brittleness oi' vthe material (requiring an undesirable amount of metal for a given size of box, as compared with the wrought-iron box) and presence of blow-holes, that the greatest care in workmanship cannot eliminate, have prevented thc use of such axle-boxes. Then I began my experiments in this direction I tried various materials, and was met in my efforts to obtain a castbox of low-grade or Bessemer steel by the cles,

statement of other metal-workers that thc ma terial could not be cast in such small artinor in the desired shape. Experiments proved the error of this, and I nally produced an axle-box of the last-named material. My improved axle-bor; is made of low-grade steel, (a specific material in the art,) opcnhearth, or Bessemer, cast to shape underapnocess closely analogous to one of these by which small castings are now made of this material, which are free from sandstreaks, free from blowholes, and homogeneous throughout. After this eastin g has been made ofthe special kind of steel, it is then 'tnrnech7 to the required smoothness and accuracy oi' bore on the inside, and, if desired, on the outside also, to better t the hub ofthe wheel. Then this axlebox is case-hardened upon the in side after the known method of case-hardenA ing iron.

In the accompanying drawing, the letter (t denotes my improved axle-bor., and I) an axlearm upon which the box tits in the usual manner.

The so-called wrought box above referred to is the one now held to be the best, and, as Compared with tl1is,my improved box, herein described, is perfectly homogeneous in texture throughout, which homogeneity is lacking, and must always be lacking, in the wrought-iron article. This homogeneity oi my low-gradesteel box makes it case-harden alike over the entire surface, whichis not the case with the wrought-iron article, and, of course, this uniformity of hardening througlr out on the inner surface makes thc axle-box wear with perfect uniformity throughout, which uniformity is absent from the wroughtiron article.

Not only has the improved axlefbox described herein thc advantages already enu merated over its known best competitors, but it is altogether cheaper in construction, as well as a better article when made, as it is superior to-the wrought (and to all cast aXleboxes) in the matter of resistance to tensile and other breaking strains.

By the term low-grade, as used in the followinfv claim I mean to restrict it to the l turned to slm io, and easeliardeued all sub- C 7 1 7 pmtlculzir and special 11i-@termi now commerstautizilly, as desor1bed,and for the purpose eizilly known by that name or as Bessemer set forth. Steel. o CHARLES H. SllIITl-l. 5 I claim as my invention- I Vtnesses:

AS au improved article ofl manufacture, :in l CHAS. L. BURDETT, axle-box made of low-grade steel, east mid ED. F. DIMOGK. 

